Add warmth to your sleep system in cool or cold conditions with our Reactor Liner. The Thermolite Pro fabric, featuring infrared-absorbing ceramic pigments and Thermolite EcoMade fibers, elevates thermal performance to the next level. The stretchy knit material ensures optimal comfort and guarantees that the Reactor fits into any sleeping bag. Additionally, the drawcord at the foot area provides ample ventilation and the versatility to move around the camp while still wearing your liner when needed.